1. Field of the Invention
The present invention relates to an apparatus and method for permanently setting pre-formed creases in a pair of pants. In particular, the present invention relates to an improved apparatus for applying a flowable curable setting material to the inside surface of the pants along pre-formed creases.
2. Description of the Related Art
At least two automated apparatuses for permanently creasing pants are known in the art. One such apparatus is disclosed in U.S. Pat. No. 4,607,589, issued Aug. 26, 1986 to Gibson, the disclosure of which is incorporated herein by reference. The Gibson apparatus comprises at least one vertical arm capable of insertion into a leg of a pair of pants, an applicator head located at an end of the arm for application of a crease setting composition, a guide means for locating the nozzle within the crease to the treated. In use the pants are lowered over the arms and the arms are moved apart to locate the applicator heads within opposing creases. The pants are then moved upwardly drawing the applicator heads down the pre-formed crease lines of each pant leg. However, the Gibson ""589 apparatus provides inaccurate resin application and is extremely complex in practice. It is not typically used in production.
Another such apparatus is disclosed in U.S. Pat. No. 4,763,600 to Saunders et al., the disclosure of which is incorporated herein by reference. The Saunders xe2x80x94600 apparatus comprises a base, a pair of horizontal support members extending from the base, and lower and upper crease blades pivoted on the support member. The free ends of the crease blades extend away from the support member and include applicator nozzles that are directed upward for the upper crease blades and downward for the lower crease blades. The horizontal crease blades of the Saunders xe2x80x94600 patent permit the entire crease length to be positioned along the upper crease blade prior to resin application. When the apparatus has received a pair of pre-creased pants over the crease blades and the lower crease blades are pivoted downward, the pants are pulled taut at the hems between the pre-formed creases and as the pants are pulled off of the crease blades, a pumping mechanism supplies a flowable, curable setting material such as silicone rubber to the applicator nozzles, which applies a coating of setting material to the inside surfaces of the pants along the creases.
However, manual pant removal of the Saunders xe2x80x94600 patent can cause uneven application of the resin if removal of the pants is sped up or slowed down. Also, the use of one actuator for the two crease blades requires exact positioning of the pants, and in production work this is not practicable.
Further, because the Saunders xe2x80x94600 patent depends upon movable crease blade assemblies with short single pivot points, there tends to be a great variation in the relative axial location of lower applicator nozzle and the upper applicator nozzle. Accordingly, the end of the pants passes the applicator nozzle of the lower crease blade some time before it would pass the applicator nozzle of the upper crease blade. This design further results in the lower applicator nozzle being arranged at a non-perpendicular angle, relative to the fabric.
Thus, what is disclosed is an apparatus for permanently setting pre-formed creases in pants. The apparatus comprises a pair of substantially horizontal parallel support members extending from a base, an upper crease blade mounted to each one of the support members, an upper applicator nozzle mounted to each of the upper crease blades and connected to a supply of setting material, a lower crease blade movably affixed via a mechanical assembly to each of the support member, a lower applicator nozzle mounted to each of the lower crease blades and connected to the supply of setting material, a pair of actuators connected to the mechanical assemblies, each of the actuators adapted to controllably move a one of the lower crease blades relative to the upper crease blades; and a controller adapted to coordinately control movement of the lower crease blades and supply of the setting material upon activation.
Optionally, the apparatus may also include a pant removal section. This section includes a support frame having a near end closest to the base and a far end further away from the base. A trolley assembly having a slider block is associated with the support frame and adapted for reciprocal movement along a guide rail in a predetermined path. A pair of grippers are attached to the trolley. A controller is adapted to coordinately control movement of the trolley assembly and actuate of the gripper. The controller also regulates the supply of the setting material to the upper and lower applicator nozzles.
According to one aspect of the invention, in the creasing section each of the mechanical assemblies comprises a control arm having a near end and a far end in relation to the base and the lower crease blade being pivotally affixed to the control arm at the far end. The control arm is further pivotally affixed to the horizontal support member at a pivot point between the near end and the far end. Each of the actuators is connected to a one of the control arms at the near end and adapted to pivot the control arm about the pivot point. Preferably, the location of the pivot point is chosen so that a ratio of a distance between the far end and the pivot point to a length of the control arm is between about ⅓ and about xc2xe, and most preferably the ratio is about two-thirds (⅔).
According to another aspect of the invention, the mechanical assembly is adapted to move the lower crease blade as a whole in a substantially downward direction.
According to a further aspect of the invention, each of the actuators comprises a pressure cylinder mounted on the base. Preferably, the actuators are air cylinders.
According to a still further aspect of the invention, one or more valves regulate the supply of resin to the applicator nozzles. Preferably, there are two valves and each of the valves independently controls the supply of the setting material to a one of the applicator nozzles. One valve controlling the two upper facing nozzles and one valve controlling the two lower.
According to another aspect of the invention, a sensor on the support member is configured to detect the presence or absence of a pair of pants and may and to detect the passing of a waistband the pair of pants. Preferably, the sensor is a photo eye mounted on a sensor support affixed to the horizontal support member.
According to a further aspect of the invention, the nozzle has the shape of an elongated oval.
According to a still further aspect of the invention, the upper crease blades have a straight top edge.
According to another aspect of the invention, in the pant removal section, a manually operated switch associated with the controller is provided that is adapted to activate the controller once a pair of pants are placed over the horizontal support members. Preferably, the manually operated switch is a foot switch.
According to a further aspect of the invention, one or more magnetic reed switches are provided along the guide rail and adapted to detect the location of the trolley assembly. The controller, informed by the switches of the relative positioning of the trolley, coordinately controls the application of the resin to the creases and the position of the crease blades.
According to a still further aspect of the invention, a pair of U-shaped brackets mounted on the trolley, each bracket having a short leg and a long leg; an air cylinder mounted between the short legs and long legs of the pair of U-shaped brackets, the air cylinder being affixed to the short legs of the pair of U-shaped brackets, the cylinder including a push rod which defines an axis perpendicular to the axis of the long legs of the U-shaped brackets; and a plate mounted on the push rod and defining a plane parallel to a plane defined by the long legs of the pair of U-shaped brackets. Upon activation, the push rod is adapted to move along the perpendicular axis.
According to another aspect of the invention, a DC gear motor mounted to the support frame including a drive shaft having a first pulley mounted thereon; a second pulley mounted on the support frame; a toothed belt suspended between the first pulley and the second pulley; and a support block affixed to the toothed belt upon which the gripper is attached. The first pulley may be arranged with respect to the second pulley so that the belt defines a plane with a downward slope or a substantially horizontal slope.
There is also provided an apparatus for permanently setting creases in pants comprising means for substantially horizontally supporting a pair of pre-creased pants; means for independently pulling each one of the pants taut at the hems between the pre-formed creases; and means for applying a flowable, curable setting material to the pre-creases in the pants while controllably removing the pants.
There is further provided a method of permanently setting creases in pants. The method comprises providing pants which are pre-creased; providing a support including a pair of fixed upper crease blades and a pair of lower crease blades pivotally mounted on the support, independently actuating a pair of the lower crease blades to pull each of the pant legs taut; applying a flowable, curable setting material to the pre-creases in the pants while controllably removing the pants.